Lecture

Electroacoustic Metamaterials

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Description

This lecture explores the development of electroacoustic metamaterials and metasurfaces, focusing on the concept of Electroacoustic Resonators. It covers the principles, properties, and applications of these materials in noise control strategies, sound absorption, and room acoustics. The presentation delves into the design and implementation of composite right/left-handed acoustic metamaterials, as well as the use of active metasurfaces for controlling sound reflection and transmission. The lecture also discusses the challenges and potential of achieving constant amplitude waveguides and the utilization of electroacoustic resonators for achieving desired sound field control.

Official source

Ontological neighbourhood

Mechanical engineering

Acoustical engineering: Architectural acoustics

Chemical engineering

Materials science: Metamaterials

Related concepts (32)

Absorption (acoustics)

Acoustic absorption refers to the process by which a material, structure, or object takes in sound energy when sound waves are encountered, as opposed to reflecting the energy. Part of the absorbed energy is transformed into heat and part is transmitted through the absorbing body. The energy transformed into heat is said to have been 'lost'. When sound from a loudspeaker collides with the walls of a room part of the sound's energy is reflected, part is transmitted, and part is absorbed into the walls.

Sound transmission class

Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. In the US, it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. Outside the US, the ISO Sound Reduction Index (SRI) is used. The STC rating very roughly reflects the decibel reduction of noise that a partition can provide. The STC is useful for evaluating annoyance due to speech sounds, but not music or machinery noise as these sources contain more low frequency energy than speech.

Noise control

Noise control or noise mitigation is a set of strategies to reduce noise pollution or to reduce the impact of that noise, whether outdoors or indoors. The main areas of noise mitigation or abatement are: transportation noise control, architectural design, urban planning through zoning codes, and occupational noise control. Roadway noise and aircraft noise are the most pervasive sources of environmental noise.

Metamaterial

A metamaterial (from the Greek word μετά meta, meaning "beyond" or "after", and the Latin word materia, meaning "matter" or "material") is any material engineered to have a property that is rarely observed in naturally occurring materials. They are made from assemblies of multiple elements fashioned from composite materials such as metals and plastics. These materials are usually arranged in repeating patterns, at scales that are smaller than the wavelengths of the phenomena they influence.

Soundproofing

Soundproofing is any means of impeding sound propagation. There are several basic ways to reduce sound: increasing the distance between source and receiver, decoupling, using noise barriers to reflect or absorb the energy of the sound waves, using damping structures such as sound baffles for absorption, or using active antinoise sound generators. Acoustic quieting and noise control can be used to limit unwanted noise.

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